Pails, for instance pails for paint, ink and other past like materials, are generally filled in pails which are closed with a lid. The lid is secured on the pail using a clamping ring.
The pail is generally provided with a lid comprising over its circumference lugs. The lid is pushed on the pail and thereafter, the lugs are bended inwardly and beyond and beneath an edge of the pail body. Accordingly, the pail is reliably secured onto the pail in effectively a single push on procedure. However, for removing the lid from the pail extensive handling is required, because all lugs have to be bended backwardly in order to detach all lugs. When closing the pail the lugs have to be bend inwardly. This well known pail provides for a relatively simple push on procedure for mounting and securing the lid on the pail body. The use by the user is far from ideal.
An alternative is represented by a pail comprising a clamping ring which clamps the lid on the free end of the pail body and grips or snaps behind a circumferential ridge in the pail body. The clamping ring is provided with a lever closure. The lever closure comprises a lever, which in the closed position imparts to the split clamping ring its minimal diameter, and in the open position, widens the clamping split ring to a larger diameter. In the larger diameter the ring may be applied onto the lid and secures the lid onto the pail by just transferring the lever from the open position to the closed position. The use of a clamping ring provides optimal handling for the user because opening and closing the pail requires a simple handling with the lever. But for the customer filling and closing pails at high rates such clamping ring closure in not suitable as it does not allow the mounting and securing the lid onto the pail body with the generally used pushed on procedure.
Still for any lid closure of the pail it is required that the pail complies with the safety required for such pails. The pail has to pass a drop test, such as for a pail of 20 liters a drop test from a height of 1.80 m onto a metal surface when dropped in a slanted position. For other pails similar stringent drop tests apply. Other tests are the hydraulic pressure test of 1.0 bar, and the air tightness test of 0.2 bar, and that stacking test.
Finally, the closure for a pail lid should also allow for tight packing and storing of the filled and closed pails, such that large numbers of pails can be stored in stacked layers on standard pallets, such as euro pallets. Similar requirements apply for pails to be filled, and for the lids to be used.